Fermentation and distillation are commercially important processes worldwide. In the United States over 100 commercial facilities produce biofuels, such as ethanol, from a variety of renewable sources. Butanol, a four carbon chain alcohol, includes 1-butanol, 2-butanol, and isobutanol all of which can be produced via fermentation. Butanol can be generated from renewable sources such as corn, sugar cane, cellulosic sources, as well as, other biomass. Butanol production, like ethanol production, implements fermentation and distillation processes to generate and concentrate the butanol for use in a variety of applications.
Butanol, for example, can be implemented as a fuel additive, a blend component to diesel fuel, a chemical reagent in the plastics industry, solvent, and a food grade extractant in the food and flavor industry. Butanol is favored as a fuel or fuel additive because it has a higher energy density than ethanol and yields CO2 and little or no SOX or NOX when used in an internal combustion engine. Additionally, butanol is less corrosive than ethanol. As the demand for butanol increases, interest in producing butanol from renewable resources such as corn, sugar cane, or cellulosic materials by fermentation is expanding.
Fermentation uses microorganisms to generate alcohol from biomass, e.g., renewable feed stocks. For example, yeast is used to convert sugars derived from corn into ethanol. Bio-derived alcohols, e.g., ethanol, butanol, produced by the fermentation are environmentally friendly as the starting materials are obtained from biological sources that can be renewed on a regular basis. Alcohols produced by fermentation can displace alcohols obtained from non-renewable sources such as oil.
Fermentation and distillation processes may be susceptible to contamination. Contaminants in a fermentation processes can diminish the microorganisms' effectiveness or reduce the population of microorganism, e.g., “kill off” microorganisms rendering them biologically inactive and thereby resulting in yield loss, lost production, and at times aborted batches. All of these can reduce the efficiency of facility and lead to waste.
Practices for cleaning fermentation and distillation facilities can be problematic and/or expensive as steam or chemicals are used. Steam, although effective, is expensive and often requires retrofitting a facility's steam generation system. Alkalines and/or acids may not be as effective for cleaning equipment in comparison to steam. Further, alkaline and acid cleaning agents may additionally pose a disposal issue.